The first high-profile spill at a natural gas hydraulic fracturing operation is proving to be no “Macondo” Gulf spill for the industry, which is pressing ahead on an sector-transforming drilling program.

Growing reliance by electricity generators on natural gas is unlikely to be weakened by reports of air and water contamination by the booming shale-gas industry, even after an April 20 gas well blowout in Pennsylvania renewed concerns that the hydraulic fracturing (“fracking”) technology used to harvest shale gas is a threat to water quality, power-industry analysts said.

Natural gas is likely to meet most of the demand growth by U.S. electric power facilities in coming years because of its domestic abundance, its environmental advantages when compared to coal and nuclear, and its ability to generate more power more quickly than wind and solar.

The plentiful domestic supply was underlined by an April 27 report from the respected Potential Gas Committee at the Colorado School of Mines, which raised its estimate for technically recoverable gas in the U.S. by 3.3% to a record 1,898 trillion cubic feet.

The new estimates show “an exceptionally strong and optimistic gas-supply picture” for the U.S., said Dr. John Curtis, director of the Potential Gas Agency, which advises the committee.

Demand for gas is also likely to be boosted by fresh worries about nuclear power generation after the Fukushima disaster prompted calls for the closure or review of America’s older nuclear plants, seven of whose operating licenses expire in the next five years.

“Natural gas has been and will be the default option for growth because it’s very difficult to site newly constructed nuclear plants,” said Raoul Leblanc, senior director for PFC Energy, a consultancy firm.

Vast domestic reserves of natural gas from deep shale deposits have recently become economic thanks to fracking technology coupled with horizontal drilling. “Supply is much more abundant than we thought,” Leblanc said.

Together with the U.S. Department of Energy’s latest estimate of proven dry-gas reserves, the U.S. has a total available future supply of 2,170 tcf, the committee said, or about 94 years’ worth at the current consumption rate.

Power generated by natural gas more than doubled to 981.8 million megawatt hours between 1996 and 2010, while coal-powered generation – accounting for 47 percent of the total — edged up to 1.85 billion MWh from 1.79 billion MWh over the same period, according to the U.S. Energy Information Administration.

Whether gas, which currently generates a fifth of U.S. power, continues to take market share from coal will depend largely on price which is expected to remain at around current levels for the next year as new supply from shale development meets growing demand, PFC’s Leblanc said. Beyond that, gas prices may see upward pressure as the most productive wells decline and producers are forced to extract the fuel from more distant locations, increasing transportation costs.

Coal-fired capacity faces a higher regulatory risk as state and federal governments demand tighter control of carbon emissions, creating an opportunity for natural gas which emits roughly half the CO2 emissions of coal when burned.

The prospect of tighter restrictions on coal-fired emissions favors natural gas and renewable fuels, but the latter are generally not cost-competitive, especially at a time when capital spending on wind and solar installations is likely to be curtailed by cash-strapped state and federal governments, Leblanc said.

Meanwhile, the boom in shale gas production is unlikely to be slowed by state or federal initiatives such as the EPA’s current national investigation into the safety of fracking, predicted Ben Montalbano, senior policy analyst at the Energy Policy Research Foundation.

“A lot of these problems are technical – they are not fundamental flaws,” he said. “I don’t think there is any larger threat to the shale-gas industry.”